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The problem of recovering a moment-determinate multivariate function $f$ via its moment sequence is studied. Under mild conditions on $f$, the point-wise and $L_1$-rates of convergence for the proposed constructions are established. The…

Statistics Theory · Mathematics 2023-12-08 Robert Mnatsakanov , Rafik Aramyan , Farhad Jafari

Image reconstruction in X ray tomography consists in determining an object from its projections. In many applications such as non destructive testing, we look for an image who has a constant value inside a region (default) and another…

Data Analysis, Statistics and Probability · Physics 2007-05-23 A. Mohammad-Djafari

In this work, we numerically investigate the inverse Robin problem of recovering a piecewise constant Robin coefficient in an elliptic or parabolic problem from the Cauchy data on a part of the boundary, a problem that commonly arises in…

Numerical Analysis · Mathematics 2025-06-10 Erik Burman , Siyu Cen , Bangti Jin , Zhi Zhou

In this paper, we consider the inverse boundary problems of recovering the time-dependent nonlinearity and damping term for a semilinear wave equation on a Riemannian manifold. The Carleman estimate and the construction of Gaussian beams…

Analysis of PDEs · Mathematics 2022-12-08 Song-Ren Fu

We consider the inverse problem of determining the metric-measure structure of collapsing manifolds from local measurements of spectral data. In the part I of the paper, we proved the uniqueness of the inverse problem and a continuity…

Analysis of PDEs · Mathematics 2024-04-26 Matti Lassas , Jinpeng Lu , Takao Yamaguchi

We prove solenoidal injectivity for the geodesic X-ray transform of tensor fields on simple Riemannian manifolds with $C^{1,1}$ metrics and non-positive sectional curvature. The proof of the result rests on Pestov energy estimates for a…

Differential Geometry · Mathematics 2024-02-15 Joonas Ilmavirta , Antti Kykkänen

In this short article, we non-perturbatively derive a recursive formula for the Green's function associated with finitely many point Dirac delta potentials in one dimension. We also extend this formula to the case for the Dirac delta…

Mathematical Physics · Physics 2017-02-28 Fatih Erman

We consider the problem of exact reconstruction of univariate functions with jump discontinuities at unknown positions from their moments. These functions are assumed to satisfy an a priori unknown linear homogeneous differential equation…

Classical Analysis and ODEs · Mathematics 2009-09-18 Dmitry Batenkov

Fix a smooth closed manifold $M$. Let $R_M$ denote the space of all pairs $(g,L)$ such that $g$ is a $C^3$ Riemannian metric on $M$ and the real number $L$ is not the length of any closed $g$-geodesics. A locally constant geodesic count…

Differential Geometry · Mathematics 2020-12-08 Eaman Eftekhary

We analyze a variational time discretization of geodesic calculus on finite- and certain classes of infinite-dimensional Riemannian manifolds. We investigate the fundamental properties of discrete geodesics, the associated discrete…

Numerical Analysis · Mathematics 2013-03-25 Martin Rumpf , Benedikt Wirth

We consider sampling strategies for a class of multivariate bandlimited functions $f$ that have a spectrum consisting of disjoint frequency bands. Taking advantage of the special spectral structure, we provide formulas relating $f$ to the…

Functional Analysis · Mathematics 2018-04-18 Christina Frederick

We propose a numerical algorithm for the reconstruction of a piecewise constant leading coefficient of an elliptic problem. The inverse problem is reduced to a shape reconstruction problem. The proposed algorithm is based on the…

Numerical Analysis · Mathematics 2020-09-02 Aleksandr E. Kolesov , Petr N. Vabishchevich

In this paper, we give a new construction of the adapted complex structure on a neighborhood of the zero section in the tangent bundle of a compact, real-analytic Riemannian manifold. Motivated by the "complexifier" approach of T. Thiemann…

Symplectic Geometry · Mathematics 2012-10-19 Brian C. Hall , William D. Kirwin

Consider a Riemannian manifold in dimension $n\geq 3$ with strictly convex boundary. We prove the local invertibility, up to potential fields, of the geodesic ray transform on tensor fields of rank four near a boundary point. This problem…

Differential Geometry · Mathematics 2020-01-08 Maarten V. de Hoop , Gunther Uhlmann , Jian Zhai

Totally geodesically embeddings of infinitely many closed 7-manifolds into 13-dimensional positively curved closed Riemannian manifolds are constructed. The problems of computing pinching constants and existence of other totally geodesical…

dg-ga · Mathematics 2008-02-03 I. A. Taimanov

In Gel'fand's inverse problem, one aims to determine the topology, differential structure and Riemannian metric of a compact manifold $M$ with boundary from the knowledge of the boundary $\partial M,$ the Neumann eigenvalues $\lambda_j$ and…

Analysis of PDEs · Mathematics 2025-04-02 Dmitri Burago , Sergei Ivanov , Matti Lassas , Jinpeng Lu

Let $M$ be a weighted manifold with boundary $\partial M$, i.e., a Riemannian manifold where a density function is used to weight the Riemannian Hausdorff measures. In this paper we compute the first and the second variational formulas of…

Differential Geometry · Mathematics 2015-06-17 Katherine Castro , César Rosales

We consider the inverse problem of recovering a continuous-domain function from a finite number of noisy linear measurements. The unknown signal is modeled as the sum of a slowly varying trend and a periodic or quasi-periodic seasonal…

Functional Analysis · Mathematics 2025-05-16 Julien Fageot

We develop a general deformation principle for families of Riemannian metrics on smooth manifolds with possibly non-compact boundary, preserving lower scalar curvature bounds. The principle is used in order to strengthen boundary…

Differential Geometry · Mathematics 2025-03-06 Helge Frerichs

We prove that the image of an isometric embedding into ${\mathbb R}^3$ of a two dimensionnal complete Riemannian manifold $(\Sigma, g)$ without boundary is a convex surface provided both the embedding and the metric $g$ enjoy a…

Differential Geometry · Mathematics 2024-08-23 Mohammad Reza Pakzad
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